BGE: How to Change Active Camera with Python?
locPoint = scene.objects['EmptyPanningEnd'].worldPosition
scene = logic.getCurrentScene()
cam1 = scene.objects['panningCamera']
cam2 = scene.objects['playerCamera']

if locPoint != cam1.worldPosition:
    scene.active_camera = cam1
else:
    scene.active_camera = cam2```

https://blender.stackexchange.com/questions/90490/how-to-switch-to-another-camera-in-blender-game-engine